KR101832643B1 - Curable composition - Google Patents

Abstract

An object of the present invention is to provide a curable composition capable of being thermally cured and capable of obtaining a cured product having low vapor permeability, low coefficient of linear expansion and low refractive index. The present invention is a curable composition characterized by containing a fluorine-containing polymer and an epoxy compound having a hydroxyl value of 100 mgKOH / g or more and a refractive index of 1.42 or less.

Description

{CURABLE COMPOSITION}

The present invention relates to a curable composition.

It is well known that a composition comprising a hydroxyl group-containing fluorine-containing polymer and a polyfunctional curing agent which reacts with a hydroxyl group is thermally cured.

For example, Patent Document 1 discloses that a coating composition obtained by dissolving a specific fluorine-containing polymer and a curing agent in an organic solvent provides a coating film excellent in workability and excellent in oil resistance and water resistance.

Patent Document 2 discloses a substrate having continuous through holes coated with a copolymer of a fluorinated ethylenic unsaturated monomer and a vinyl alcohol at least a part of the inside of the substrate so that the -OH component is added so that the copolymer is not solubilized by any solvent Crosslinking with a polyfunctional epoxide.

Japanese Patent Application Laid-Open No. 59-174657 Japanese Patent Publication No. 9-504994

Disclosure of the Invention It is an object of the present invention to provide a curable composition capable of being thermally cured and capable of obtaining a cured product having a low vapor permeability, a low linear expansion coefficient and a low refractive index.

The present inventors have found that when an epoxy compound is selected as a crosslinking agent for crosslinking a fluorine-containing polymer having a hydroxyl value of 100 mgKOH / g or more and a refractive index of 1.42 or less, the cured product obtained by crosslinking has a low vapor- The present invention has been accomplished on the basis of these findings.

That is, the present invention is a curable composition comprising a fluorine-containing polymer and an epoxy compound having a hydroxyl value of 100 mgKOH / g or more and a refractive index of 1.42 or less.

The curable composition preferably further comprises an acid anhydride.

The fluorine-containing polymer preferably has a fluorine-containing olefin unit and a vinyl alcohol unit.

The content of the fluorine-containing olefin unit in the fluorine-containing polymer is preferably 30 mol% or more.

Wherein the fluorine-containing polymer is represented by the following formula (1):

(Wherein X ¹ , X ² and X ³ are the same or different and each represents H, F or a fluoroalkyl group, R ¹ represents a divalent organic group which may have an ether bond, x represents 0 or 1) < / RTI >

The curable composition preferably further comprises a curing accelerator.

The epoxy compound is liquid at 25 占 폚 and the ratio of the dispersion term, the polarity term and the hydrogen bonding term in the solubility parameter is different from the point A (86,7,7), the point B (70,25 , 5), points C (50, 25, 25), points D (50, 5, 45) and points E (82, 5, 13).

The epoxy compound is preferably at least one compound selected from the group consisting of the following compounds.

The curable composition preferably does not contain an organic solvent having no radical reactive group.

Since the curable composition of the present invention has the above-described constitution, it is possible to obtain a cured product having a low vapor permeability, a low linear expansion coefficient and a low refractive index, which is a composition capable of being thermally cured.

1 is a three-circle diagram showing the ratio of the dispersion term, the polarity term and the hydrogen bonding term in the solubility parameter of the epoxy compound.

Hereinafter, the present invention will be described in detail.

The curable composition of the present invention comprises a fluorine-containing polymer having a hydroxyl value of 100 mgKOH / g or more and a refractive index of 1.42 or less. Thus, a cured product having low vapor permeability, high modulus of elasticity, low coefficient of linear expansion and low refractive index can be obtained.

In this specification, the cured product has a low refractive index means that the refractive index of the cured product is 1.55 or less.

If the hydroxyl value of the fluorine-containing polymer is too low, the solubility with the epoxy compound may be deteriorated. The hydroxyl value is 100 mgKOH / g or more, preferably 110 mgKOH / g or more, and more preferably 120 mgKOH / g or more. The hydroxyl value is preferably 700 mgKOH / g or less, more preferably 650 mgKOH / g or less, still more preferably 600 mgKOH / g or less, still more preferably 550 mgKOH / g or less, Particularly preferably 500 mgKOH / g or less.

The hydroxyl value is a value measured according to JIS K 0070-1992.

If the refractive index of the fluorine-containing polymer is too high, a cured product having a low refractive index may not be obtained. The refractive index is 1.42 or less, preferably 1.41 or less, more preferably 1.40 or less. The refractive index is preferably 1.34 or more, more preferably 1.35 or more, and further preferably 1.36 or more.

The refractive index is a value measured using Abbe's refractometer manufactured by Atago Kogaku Kikai Seisakusho Co., Ltd. at 25 ° C with a sodium D line as a light source.

Examples of the fluorine-containing polymer include fluorine-containing olefin units and vinyl alcohol units (-CH ₂ -CH (OH) -) such as fluorine-containing olefin units and polymers having fluorine atom and having hydroxyl value and refractive index within the above- Containing polymer (hereinafter also referred to as fluorine-containing polymer (I)). The fluorine-containing polymer (I) is a fluorine-containing polymer capable of increasing the fluorine content and the glass transition temperature at a relatively low cost without using a monomer having a high functional group. Thus, a cured product having low vapor permeability, high modulus of elasticity, low coefficient of linear expansion, and low refractive index can be obtained at low cost from the curable composition of the present invention.

The fluorine-containing olefin unit represents a polymerization unit based on a fluorine-containing olefin. The fluorine-containing olefin is a monomer having a fluorine atom.

Examples of the fluorine-containing olefin, tetrafluoroethylene [TFE], vinylidene fluoride [VdF], a chlorotrifluoroethylene ethylene [CTFE], a vinyl fluoride, hexafluoropropylene [HFP], hexafluoro-isobutene, CH ₂ = ^{_{CZ 1 (CF 2) n1 Z}} 2 ( in the formula, Z ¹ is H, F or Cl, Z ² is H, F or Cl, n1 is an integer of 1 to 10), a monomer represented by, CF ₂ = CF-oR (Alkyl vinyl ether) [PAVE] and CF ₂ ═CF-OCH ₂ -R _F ² (alkyl vinyl ether) represented by _F ¹ (wherein R _F ¹ represents a perfluoroalkyl group having 1 to 8 carbon atoms) Is preferably at least one fluorine-containing olefin selected from the group consisting of alkyl perfluorovinyl ether derivatives represented by the following general formula (wherein R _F ² is a perfluoroalkyl group having 1 to 5 carbon atoms).

As the ^{_{CH 2 = CZ 1 (CF 2}} ) _n1 monomer represented by Z ^2, and the like can be _{CH 2 = CFCF 3, CH 2} = CHCF 3, CH 2 = CFCHF 2, CH 2 = CClCF 3.

Examples of the PAVE include perfluoro (methyl vinyl ether) [PMVE], perfluoro (ethyl vinyl ether) PEVE, perfluoro (propyl vinyl ether) PPVE, and perfluoro (butyl vinyl ether) Among them, PMVE, PEVE or PPVE is more preferable.

As the alkyl perfluorovinyl ether derivative, R _F ² is preferably a perfluoroalkyl group having 1 to 3 carbon atoms, more preferably CF ₂ ═CF-OCH ₂ -CF ₂ CF ₃ .

The fluorine-containing olefin is more preferably at least one selected from the group consisting of TFE, CTFE and HFP, and more preferably TFE.

The content of the fluorine-containing olefin unit in the fluorine-containing polymer (I) is preferably 30 mol% or more, the content of the fluorine-containing olefin unit is 30 mol% or more and 80 mol% Unit is more preferably 20 mol% or more and 70 mol% or less. When the content of each monomer unit in the fluorine-containing polymer (I) is in this range, a cured product having better water vapor permeability, high modulus of elasticity, low coefficient of linear expansion and low refractive index can be obtained. The content of each monomer unit is preferably 40 mol% or more and 80 mol% or less, more preferably 20 mol% or more and 60 mol% or less, and more preferably 40 mol% or more and 75 mol , More preferably from 25 mol% to 60 mol%, further more preferably from 45 mol% to 70 mol% of the fluorine-containing olefin unit and from 30 mol% to 55 mol% of the vinyl alcohol unit Particularly preferred.

The fluorine-containing polymer (I) preferably has an alternating ratio of the fluorine-containing olefin unit and the vinyl alcohol unit of less than 95%. When the alternation ratio is in this range, the solubility in the epoxy compound is improved. , More preferably 90% or less, and particularly preferably 80% or less. Further, it is preferably at least 30%, more preferably at least 35%, and even more preferably at least 40%. If the alternation ratio is too low, heat resistance may be lowered, which is not preferable.

The alternating ratio between the fluorine-containing olefin unit and the vinyl alcohol unit is determined by ¹ H-NMR measurement of the fluorine-containing polymer (I) using a solvent in which the fluorine-containing polymer (I) such as a heavy acetone is dissolved, It can be calculated as the alternation rate of three chains from the following expression.

(%) = C / (A + B + C) x 100

A: the number of V combined with two V as in -V-V-V-

B: Number of V coupled to V and T as in -V-V-T-

C: Number of V coupled to two Ts, such as -T-V-T-

(T: fluorine-containing olefin unit, V: vinyl alcohol unit)

The number of V units of A, B and C is calculated from the intensity ratio of H of the main chain bonded to the tertiary carbon of the vinyl alcohol unit (-CH ₂ -CH (OH) -) of the ¹ H-NMR measurement. The estimation of the intensity ratio of H in the main chain by ¹ H-NMR measurement was carried out with the fluorine-containing polymer before the hydroxylation.

The fluorine-containing polymer (I) is a vinyl ester monomer unit represented by -CH ₂ -CH (O (C═O) R) - (wherein R represents a hydrogen atom or a hydrocarbon group having 1 to 17 carbon atoms) . Thus, the fluorine-containing polymer (I) having a fluorine-containing olefin unit, a vinyl alcohol unit and a vinyl ester monomer unit is also a preferred embodiment of the present invention. Also, a fluorine-containing olefin / vinyl alcohol / vinyl ester monomer copolymer substantially containing only a fluorine-containing olefin unit, a vinyl alcohol unit and a vinyl ester monomer unit is also a suitable embodiment of the present invention.

The vinyl ester monomer unit is a monomer unit represented by -CH ₂ -CH (O (C = O) R) - (wherein R represents a hydrogen atom or a hydrocarbon group having 1 to 17 carbon atoms) , R is preferably an alkyl group having from 1 to 11 carbon atoms, more preferably an alkyl group having from 1 to 5 carbon atoms. And particularly preferably an alkyl group having 1 to 3 carbon atoms.

As the vinyl ester monomer unit, for example, monomer units derived from the following vinyl esters are exemplified.

There may be mentioned vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl isobutyrate, vinyl valerate, vinyl isovalerate, vinyl caprate, vinyl heptylate, vinyl caprylate, vinyl pivalate, vinyl caprylate, caprylic acid (Vinyl chloride), vinyl stearate, vinyl octylate, Veova-9 (manufactured by Showa Shell Sekiyu K.K.), polyvinyl butyrate, polyvinyl butyrate, , Veova-10 (manufactured by Showa Shell Sekiyu Co., Ltd.), vinyl benzoate, vinyl versatate.

Among these, monomer units derived from vinyl acetate, vinyl propionate, vinyl versatate and vinyl stearate are preferable. More preferably, it is a vinyl acetate monomer unit, a vinyl propionate monomer unit, or a vinyl stearate monomer unit, and more preferably a vinyl acetate monomer unit.

When the fluorine-containing polymer (I) has a fluorine-containing olefin unit, a vinyl alcohol unit and a vinyl ester monomer unit, the content of each monomer unit is preferably 30 mol% or more and 80 mol% or less, It is preferable that the alcohol unit is 17 mol% or more and less than 70 mol%, and the vinyl ester monomer unit is more than 0 mol% and 53 mol% or less. When the content of each monomer unit is in this range, a cured product having better water vapor permeability, high modulus of elasticity, low coefficient of linear expansion and low refractive index can be obtained. The content of each monomer unit is preferably from 35 mol% to 80 mol%, the vinyl alcohol unit is from 17 mol% to less than 65 mol%, the vinyl ester monomer unit is from more than 0 mol% to 48 mol% More preferably 35 mol% or more and 75 mol% or less of the fluorine-containing olefin unit, 17 mol% or more and 60 mol% or less of the vinyl alcohol unit, and 5 mol% or more and 48 mol% or less of the vinyl ester monomer unit , More preferably 45 mol% or more to 70 mol% or less of the fluorine-containing olefin unit, 17 mol% or more to 50 mol% or less of the vinyl alcohol unit, and 5 mol% or more and 38 mol% or less of the vinyl ester monomer unit.

When the fluorine-containing polymer (I) has a fluorine-containing olefin unit, a vinyl alcohol unit and a vinyl ester monomer unit, the alternating ratio between the fluorine-containing olefin unit and the vinyl alcohol unit and the vinyl ester monomer unit is preferably less than 95% . When the alternation ratio is in this range, the solubility in the epoxy compound is improved. , More preferably 90% or less, and particularly preferably 80% or less. Further, it is preferably at least 30%, more preferably at least 35%, and even more preferably at least 40%. If the alternation ratio is too low, heat resistance may be lowered, which is not preferable.

The alternation ratio of the fluorine-containing olefin unit with the vinyl alcohol unit and the vinyl ester monomer unit can be determined by ¹ H-NMR measurement of the fluorine-containing polymer (I) using a solvent in which the fluorine- And can be calculated as the alternation rate of three chains from the following expression.

(%) = C / (A + B + C) x 100

A: the number of V combined with two V as in -V-V-V-

B: Number of V coupled to V and T as in -V-V-T-

C: Number of V coupled to two Ts, such as -T-V-T-

(T: fluorine-containing olefin unit, V: vinyl alcohol unit or vinyl ester monomer unit)

A, B, the number of units of V are C, ¹ H-NMR of the vinyl alcohol units of measurement _{(-CH 2 -CH (OH) -} ) , and a vinyl ester monomer units, _{(-CH 2 -CH (O (C} = O) R) -) is calculated from the intensity ratio of H of the main chain bonded to the tertiary carbon of H. The estimation of the intensity ratio of H in the main chain by ¹ H-NMR measurement was carried out with the fluorine-containing polymer before the hydroxylation.

The fluorine-containing polymer (I) may have monomer units other than the fluorine-containing olefin unit, the vinyl alcohol unit and the vinyl ester monomer unit within the range that does not impair the effect of the present invention.

Examples of the other monomer include monomers which do not contain fluorine atoms (except for the vinyl alcohol and vinyl ester monomers), such as ethylene, propylene, 1-butene, 2-butene, vinyl chloride, vinylidene chloride, vinyl At least one fluorine-free ethylenic monomer selected from the group consisting of an ether monomer, an unsaturated carboxylic acid, and an unsaturated carboxylic acid is preferable.

The total content of the other monomer units is preferably 0 to 50 mol%, more preferably 0 to 40 mol%, still more preferably 0 to 30 mol%, based on the total monomer units of the fluorine-containing polymer (I) Do.

In the present specification, the content of each monomer unit constituting the fluorine-containing polymer (I) can be calculated by appropriately combining NMR, FT-IR, and elemental analysis according to the types of monomers.

The weight average molecular weight of the fluorine-containing polymer (I) is not particularly limited, but is preferably 9,000 or more, and more preferably 10,000 or more. More preferably from 20,000 to 2,000,000, and particularly preferably from 30,000 to 1,000,000.

The weight average molecular weight can be determined by gel permeation chromatography (GPC).

The fluorine-containing polymer (I) can be produced by subjecting a copolymer having a fluorine-containing olefin unit and a vinyl ester monomer unit to hydroxylation as described later. That is, a copolymer obtained by subjecting a copolymer having a fluorine-containing olefin unit and a vinyl ester monomer unit to fluorine-containing polymer (I) to hydroxylation is also one of preferred embodiments of the present invention.

Hereinafter, a method for producing the fluorine-containing polymer (I) will be described.

Usually, the fluorine-containing polymer (I) can be produced by copolymerizing a fluorine-containing olefin such as tetrafluoroethylene with a vinyl ester monomer such as vinyl acetate, and then subjecting the obtained copolymer to hydroxylation. When the alternation ratio of the fluorine-containing polymer (I) is less than 95%, it is preferable to carry out the polymerization under the condition that the composition ratio of the fluorine-containing olefin and the vinyl ester monomer is kept substantially constant. That is, the above-mentioned fluorine-containing polymer (I) is a step of polymerizing under a condition of keeping the composition ratio of the fluorine-containing olefin and the vinyl ester monomer substantially constant, thereby obtaining a copolymer having a fluorine-containing olefin unit and a vinyl ester monomer unit, And a step of obtaining a copolymer having a fluorine-containing olefin unit and a vinyl alcohol unit by subjecting the resulting copolymer to hydroxylation.

Examples of the vinyl ester monomer include vinyl formate, vinyl acetate, vinyl propionate, vinyl butyrate, vinyl isobutyrate, vinyl valerate, vinyl isovalerate, vinyl caproate, vinyl heptylate, vinyl caprylate, vinyl pivalate, Polyvinyl pyrrolidone, vinyl palmitate, vinyl stearate, vinyl stearate, vinyl octylate, Veova-9 (manufactured by Showa Shell Sekiyu Co., Ltd.) (Manufactured by Showa Shell Sekiyu Co., Ltd.), vinyl benzoate, vinyl versatate and the like. Of these, vinyl acetate, vinyl propionate , And vinyl versatate are preferably used.

As the vinyl ester monomer, one kind may be used, or two or more kinds may be used in combination.

Examples of the method of copolymerizing the fluorine-containing olefin with the vinyl ester monomer include a polymerization method such as solution polymerization, bulk polymerization, emulsion polymerization and suspension polymerization, and from the viewpoint of industrial ease of implementation, emulsion polymerization, solution polymerization, , But the present invention is not limited thereto.

In the emulsion polymerization, solution polymerization, or suspension polymerization, a polymerization initiator, a solvent, a chain transfer agent, a surfactant, a dispersant, and the like can be used.

The solvent used in the solution polymerization is preferably one that is capable of dissolving the fluorine-containing olefin and the vinyl ester monomer and the fluorine-containing polymer (I) to be synthesized, and examples thereof include n-butyl acetate, t- , Esters such as methyl acetate and propyl acetate; Ketones such as acetone, methyl ethyl ketone, and cyclohexanone; Aliphatic hydrocarbons such as hexane, cyclohexane, and octane; Aromatic hydrocarbons such as benzene, toluene and xylene; Alcohols such as methanol, ethanol, t-butanol and isopropanol; Cyclic ethers such as tetrahydrofuran and dioxane; A fluorine-containing solvent such as HCFC-225; Dimethyl sulfoxide, dimethyl formamide, or a mixture thereof.

Examples of the solvent used in the emulsion polymerization include water, a mixed solvent of water and alcohol, and the like.

Examples of the polymerization initiator include an oil-soluble radical polymerization initiator represented by peroxycarbonates such as diisopropyl peroxydicarbonate (IPP) and di-n-propyl peroxydicarbonate (NPP) Soluble radical polymerization initiators such as ammonium salts, potassium salts and sodium salts of persulfuric acid, perboric acid, perchloric acid, superphosphoric acid and percarbonic acid, and the like can be used. Particularly, in emulsion polymerization, ammonium persulfate and potassium persulfate are preferable.

As the surfactant, a commonly used surfactant can be used. For example, a nonionic surfactant, an anionic surfactant, and a cationic surfactant can be used. A fluorine-containing surfactant may also be used.

Examples of the dispersant used in the suspension polymerization include water-soluble cellulose ethers such as partially saponified polyvinyl acetate, methylcellulose, hydroxyethylcellulose, hydroxypropylcellulose and hydroxypropylmethylcellulose, which are used in ordinary suspension polymerization, , Gelatin, and the like. The suspension polymerization is carried out under the condition that the ratio of water / monomers is usually from 1.5 / 1 to 3/1, and 0.01 to 0.1 parts by mass is used with respect to 100 parts by mass of the monomer. If necessary, a pH buffer such as polyphosphate may also be used.

Examples of the chain transfer agent include hydrocarbons such as ethane, isopentane, n-hexane, and cyclohexane; Aromatic compounds such as toluene and xylene; Ketones such as acetone; Acetic acid esters such as ethyl acetate and butyl acetate; Alcohols such as methanol and ethanol; Mercaptans such as methyl mercaptan; And halogenated hydrocarbons such as carbon tetrachloride, chloroform, methylene chloride and methyl chloride.

The addition amount of the chain transfer agent may vary depending on the chain transfer constant of the compound used, but is usually in the range of 0.001 to 10 mass% with respect to the polymerization solvent.

The polymerization temperature is not particularly limited as long as the composition ratio of the fluorine-containing olefin and the vinyl ester monomer during the reaction is almost constant, and may be 0 to 100 ° C.

The polymerization pressure may be within a range in which the composition ratio of the fluorine-containing olefin and the vinyl ester monomer during the reaction is almost constant, and may be 0 to 10 MPaG.

The hydroxylation of the acetate group derived from vinyl acetate is well known in the art and can be performed by a conventionally known method such as alcoholysis or hydrolysis using an acid or base. Among them, the hydrolysis using a base is generally called saponification. In this specification, hereinafter, the hydroxylation of the vinyl ester monomer is referred to as saponification regardless of the method. By this saponification, the acetate group (-OCOCH ₃ ) is converted into a hydroxyl group (-OH). Similarly, other vinyl ester monomers can be saponified by a conventionally known method to obtain a hydroxyl group.

The degree of saponification in the case of saponifying a copolymer having a fluorine-containing olefin unit and a vinyl ester monomer unit to obtain the fluorine-containing polymer (I) of the present invention is not particularly limited as long as the degree of saponification of the respective monomer units Is preferably in a range within the above-mentioned range. Specifically, it is preferably not less than 50%, more preferably not less than 60%, and even more preferably not less than 70%.

The degree of saponification is calculated from the following formula by IR measurement or ¹ H-NMR measurement of the fluorine-containing polymer (I).

Saponification degree (%) = D / (D + E) x 100

D: The number of vinyl alcohol units in the fluorine-containing polymer (I)

E: the number of vinyl ester monomer units in the fluorine-containing polymer (I)

The fluorine-containing polymer (I) in the present invention is a copolymer of a vinyl ether monomer (CH ₂ ═CH-OR) (hereinafter simply referred to as "vinyl ether monomer") having a protective group (R) bonded thereto which can be converted into a vinyl alcohol by a deprotection reaction with a fluorine- Vinyl ether monomer) to obtain a fluorine-containing olefin / vinyl ether copolymer, and a step of obtaining the fluorine-containing olefin / vinyl alcohol copolymer by deprotecting the fluorine-containing olefin / vinyl ether copolymer Can also be obtained by a manufacturing method.

The method of copolymerizing the fluorine-containing olefin with the vinyl ether monomer and the method of deprotecting the fluorine-containing olefin / vinyl ether copolymer are well known in the art, and conventionally known methods can also be carried out in the present invention. By carrying out the deprotection reaction of the fluorine-containing olefin / vinyl ether copolymer, the protecting group alkoxy group is converted into the hydroxyl group to obtain the fluorine-containing olefin / vinyl alcohol copolymer.

The fluorine-containing olefin / vinyl ether copolymer obtained by copolymerizing the fluorine-containing olefin and the vinyl ether monomer has (40 to 60) molar ratio of the fluorine-containing olefin and the vinyl ether monomer / (vinyl ether monomer) / / (60 to 40), and more preferably (45 to 55) / (55 to 45). The fluorine-containing polymer (I) in which the molar ratio is in the above-mentioned range and the deprotection is within the range described later, in which the molar ratio of the respective polymerized units is in the above-mentioned range can be produced.

The above-mentioned deprotection of the fluorine-containing olefin / vinyl ether copolymer is preferably carried out so that the degree of deprotection is 1 to 100%, more preferably 30 to 100%.

The degree of deprotection is determined by ¹ H-NMR from a proton integral value derived from a tert-butyl group (-C (CH ₃ ) ₃ ) in the vicinity of 1.0 to 1.3 ppm before and after deprotection and a proton integral value from 2.2 to 2.7 ppm Can be measured by quantifying the proton integral value derived from the methylene group (-CH ₂ -CH-).

^& Lt; ¹ > H-NMR: GEMINI-300

It is preferable that the vinyl ether monomer does not contain a fluorine atom. The vinyl ether monomer is not particularly limited as long as it is deprotected, but t-butyl vinyl ether is preferable because it is easy to obtain.

When the fluorine-containing polymer (I) has a fluorine-containing olefin unit, a vinyl alcohol unit and a vinyl ether unit, the alternating ratio of the fluorine-containing olefin unit and the vinyl alcohol unit and the vinyl ether unit is preferably less than 95%. When the alternation ratio falls within this range, an effect that solvent solubility is high is obtained. Further, it is preferably at least 30%, more preferably at least 35%, and even more preferably at least 40%. When the alternation ratio is low, the heat resistance is lowered, which is not preferable.

The alternating ratio between the fluorine-containing olefin unit and the vinyl alcohol unit and the vinyl ether unit is determined by ¹ H-NMR measurement of the fluorine-containing polymer (I) using a solvent in which the fluorine-containing polymer (I) such as acetone is dissolved , It can be calculated as an alternation rate of three chains from the following expression.

(%) = C / (A + B + C) x 100

A: the number of V combined with two V as in -V-V-V-

B: Number of V coupled to V and T as in -V-V-T-

C: Number of V coupled to two Ts, such as -T-V-T-

(T: fluorine-containing olefin unit, V: vinyl alcohol unit or vinyl ether unit)

The number of units of V A, B, C, ^1-vinyl alcohol units of the H-NMR measurement _{(-CH 2 -CH (OH) -} ) , and the tertiary carbon of the vinyl ether unit (-CH ₂ -CH (OR)) Is calculated from the intensity ratio of H of the main chain bonded to the main chain. The estimation of the intensity ratio of H in the main chain by ¹ H-NMR measurement was carried out with the fluorine-containing polymer before the hydroxylation.

Examples of the method of copolymerizing the fluorine-containing olefin with the vinyl ether monomer include a polymerization method such as solution polymerization, bulk polymerization, emulsion polymerization, suspension polymerization and the like. From the standpoint of industrial ease of implementation, But it is not limited thereto.

In the emulsion polymerization, solution polymerization, or suspension polymerization, a polymerization initiator, a solvent, a chain transfer agent, a surfactant, a dispersant, and the like may be used.

The solvent used in the solution polymerization is preferably one which is capable of dissolving the fluorine-containing olefin and the vinyl ether monomer and the fluorine-containing polymer (I) to be synthesized, and examples thereof include n-butyl acetate, t- , Esters such as methyl acetate and propyl acetate; Ketones such as acetone, methyl ethyl ketone, and cyclohexanone; Aliphatic hydrocarbons such as hexane, cyclohexane, and octane; Aromatic hydrocarbons such as benzene, toluene and xylene; Alcohols such as methanol, ethanol, t-butanol and isopropanol; Cyclic ethers such as tetrahydrofuran and dioxane; A fluorine-containing solvent such as HCFC-225; Dimethyl sulfoxide, dimethyl formamide, or a mixture thereof.

Examples of the solvent used in the emulsion polymerization include water, a mixed solvent of water and alcohol, and the like.

Examples of the polymerization initiator include an oil-soluble radical polymerization initiator represented by peroxycarbonates such as diisopropyl peroxydicarbonate (IPP) and di-n-propyl peroxydicarbonate (NPP) Soluble radical polymerization initiators such as ammonium salts, potassium salts and sodium salts of persulfuric acid, perboric acid, perchloric acid, superphosphoric acid and percarbonic acid, and the like can be used. Particularly, in emulsion polymerization, ammonium persulfate and potassium persulfate are preferable.

As the surfactant, a commonly used surfactant can be used. For example, a nonionic surfactant, an anionic surfactant, and a cationic surfactant can be used. A fluorine-containing surfactant may also be used.

Examples of the dispersant used in the suspension polymerization include water-soluble cellulose ethers such as partially saponified polyvinyl acetate, methylcellulose, hydroxyethylcellulose, hydroxypropylcellulose and hydroxypropylmethylcellulose, which are used in ordinary suspension polymerization, , Gelatin, and the like. The suspension polymerization is carried out under the condition that the ratio of water / monomers is usually from 1.5 / 1 to 3/1, and 0.01 to 0.1 parts by mass is used with respect to 100 parts by mass of the monomer. If necessary, a pH buffer such as polyphosphate may also be used.

Examples of the chain transfer agent include hydrocarbons such as ethane, isopentane, n-hexane, and cyclohexane; Aromatic compounds such as toluene and xylene; Ketones such as acetone; Acetic acid esters such as ethyl acetate and butyl acetate; Alcohols such as methanol and ethanol; Mercaptans such as methyl mercaptan; And halogenated hydrocarbons such as carbon tetrachloride, chloroform, methylene chloride and methyl chloride.

The addition amount of the chain transfer agent may vary depending on the chain transfer constant of the compound used, but is usually in the range of 0.001 to 10 mass% with respect to the polymerization solvent.

The polymerization temperature is not particularly limited as long as the composition ratio of the fluorine-containing olefin and the vinyl ether monomer during the reaction is substantially constant, and may be 0 to 100 占 폚.

The polymerization pressure may be in a range such that the composition ratio of the fluorine-containing olefin and the vinyl ether monomer during the reaction is almost constant, and may be 0 to 10 MPaG.

The deprotection of the vinyl ether monomer can be carried out by a conventionally known method such as acid, heat, and light. By this deprotection, the leaving group (for example, -C (CH ₃ ) ₃ ) can be substituted with hydrogen to obtain a hydroxyl group.

The degree of deprotection in the case of obtaining the fluorine-containing polymer (I) of the present invention by deprotecting the copolymer having the fluorine-containing olefin unit and the vinyl ether monomer unit is preferably a degree of deprotection of the fluorine-containing polymer (I) It is sufficient that the content ratio of each monomer unit falls within the above-mentioned range. Specifically, it is preferably not less than 50%, more preferably not less than 60%, and even more preferably not less than 70%.

The degree of deprotection is calculated from the following formula by IR measurement of the fluorine-containing polymer (I) or ¹ H-NMR measurement described above.

Degree of protection (%) = D / (D + E) x 100

D: The number of vinyl alcohol units in the fluorine-containing polymer (I)

E: the number of vinyl ether monomer units in the fluorine-containing polymer (I)

As the fluorine-containing polymer in the present invention,

(Wherein X ¹ , X ² and X ³ are the same or different and each represents H, F or a fluoroalkyl group, R ¹ represents a divalent organic group which may have an ether bond, x represents 0 or Containing polymer (hereinafter also referred to as fluorine-containing polymer (II)) having a unit based on a monomer represented by the following formula (1) (hereinafter also referred to as monomer (1) When the fluorine-containing polymer (II) is used, a cured product having a lower refractive index can be obtained.

X ¹ , X ² and X ³ in the above formula (1) are the same or different and each represents H, F or fluoroalkyl group. The fluoroalkyl group preferably has 1 to 5 carbon atoms, more preferably 1 to 3 carbon atoms, and even more preferably 1 to 2 carbon atoms. Examples of the fluoroalkyl group include CF ₃ and -CF ₂ CF ₃ .

X ¹ , X ² and X ³ are preferably F.

R ¹ in the above formula (1) represents a divalent organic group which may have an ether bond. The organic group preferably has 1 to 20 carbon atoms, more preferably 1 to 15 carbon atoms, and even more preferably 2 to 10 carbon atoms. The organic group preferably has a fluorine atom. The organic group is more preferably a fluoroalkylene group which may have an ether bond, and more preferably a fluoroalkylene group having an ether bond.

Specific examples of the R ¹ include -CF (CF ₃ ) - (CF ₂ -O-CF (CF ₃ )) _n -CH ₂ - (wherein n represents an integer of 0 to 10) . Among them, -CF (CF ₃ ) -CF ₂ -O-CF (CF ₃ ) -CH ₂ -, -CF (CF ₃ ) -CH ₂ -, -CF (CF ₃ ) -CF ₂ -O-CF _{CF 3) -CF 2 -O-CF} (CF 3) -CH 2 - are preferred.

In the above formula (1), x is 0 or 1. x is preferably 1.

Examples of the monomer (1), in _{particular, CH 2 = CF-CF 2} -O-CF (CF 3) -CF 2 -O-CF (CF 3) -CH 2 -OH, CH 2 = CF-CF 2 - _{O-CF (CF 3) -CH} 2 -OH, CH 2 = CF-CF 2 -O-CF (CF 3) - (CF 2 -O-CF (CF 3)) 2 -CH 2 -OH, CH 2 = CF-CF ₂ -O-CF (CF ₃ ) - (CF ₂ -O-CF (CF ₃ )) ₃ -CH ₂ -OH.

Among _{them, CH 2 = CF-CF 2} -O-CF (CF 3) -CF 2 -O-CF (CF 3) -CH 2 -OH, CH 2 = CF-CF 2 -O-CF (CF 3) -CH ₂ -OH is preferred.

In the fluorine-containing polymer (II), the content of the monomer (1) unit based on the monomer (1) is preferably 40 to 100 mol%, more preferably 60 to 100 mol% And more preferably 80 to 100 mol%.

The fluorine-containing polymer (II) may contain only the above-mentioned monomer (1) unit or may further include a unit based on a monomer copolymerizable with the monomer (1).

As the monomer copolymerizable with the monomer (1), a fluorine-containing olefin (excluding the monomer (1)) is preferable. As the fluorine-containing olefin, the fluorine-containing olefin exemplified for the fluorine-containing polymer (I) can be exemplified. Among them, at least one kind selected from the group consisting of TFE, CTFE and HFP is more preferable and TFE is more preferable .

When the fluorine-containing polymer (II) contains a unit based on a fluorine-containing olefin, the content of each monomer unit is preferably 40 mol% or more and 99 mol% or less, and the fluorine-containing olefin unit is 1 mol , More preferably not less than 60 mol%, more preferably not less than 60 mol% and not more than 99 mol% of the monomer (1) unit and not less than 1 mol% and not more than 40 mol% of the fluorine-containing olefin unit, More preferably 80 mol% or more and 99 mol% or less, and the fluorine-containing olefin unit is more preferably 1 mol% or more and 20 mol% or less.

Examples of the monomer copolymerizable with the monomer (1) include monomers not containing a fluorine atom. Examples of the monomer that does not contain a fluorine atom include at least one kind of monomer selected from the group consisting of ethylene, propylene, 1-butene, 2-butene, vinyl chloride, vinylidene chloride, vinyl ether monomer and unsaturated carboxylic acid The fluorine-free ethylenic monomer is preferred.

The total content of the units based on the monomer containing no fluorine atom is preferably from 0 to 50 mol%, more preferably from 0 to 40 mol%, and most preferably from 0 to 50 mol% of the total monomer units of the fluorine-containing polymer (II) By mole to 30% by mole.

In the present specification, the content of each monomer unit constituting the fluorine-containing polymer (II) can be calculated by appropriately combining NMR, FT-IR and elemental analysis according to the types of monomers.

The weight average molecular weight of the fluorine-containing polymer (II) is not particularly limited, but is preferably 9,000 or more, and more preferably 10,000 or more. More preferably from 20,000 to 2,000,000, and particularly preferably from 30,000 to 1,000,000.

The weight average molecular weight can be determined by gel permeation chromatography (GPC).

The curable composition of the present invention comprises an epoxy compound. As the epoxy compound, a compound having at least one, and preferably at least two, oxirane rings in the molecule can be used. Examples of the epoxy compound include compounds represented by the following general formula (2-1):

(Wherein T ¹ is the same or different and is H, F, an alkyl group which may have a substituent or a fluorine-containing alkyl group which may have a substituent) and a group represented by the following formula (2-2):

(Wherein M is an aliphatic ring or a heteroaliphatic ring, T ² is the same or different and is H, F, an alkyl group which may have a substituent or a fluorine-containing alkyl group which may have a substituent, and m is an integer of 3 or more) Is preferably a compound having at least one group selected from the group consisting of two or more groups in the molecule.

In the group represented by the general formula (2-1), T ¹ is the same or different and represents H, F, an alkyl group which may have a substituent or a fluorine-containing alkyl group which may have a substituent, Alkyl group which may have a substituent "includes a straight, branched or cyclic alkyl group of 1 to 12 carbon atoms, and examples thereof include a methyl group, ethyl group, n-propyl group, isopropyl group, Butyl group, isobutyl group, t-butyl group, pentyl group, cyclopentyl group, hexyl group, cyclohexyl group, octyl group and cyclodecyl group. Among them, an alkyl group having 1 to 8 carbon atoms is preferable.

The substituent of the "alkyl group which may have a substituent" is not particularly limited as long as it does not adversely affect the performance of the fluorine-containing polymer of the present invention. Examples thereof include -OH, -COOH, -COOCH ₃ , -NH ₂ , -COOCH ₂ CH ₃ , and the like.

When the alkyl group which may have a substituent has a substituent, it may have one substituent or two or more substituents, and examples thereof include a form in which at least one of the above-exemplified substituents has 1 to 3 substituents .

Examples of the fluorine-containing alkyl group of the "fluorine-containing alkyl group which may have a substituent (s)" in the above-mentioned T ¹ include linear, branched or cyclic fluorine-containing alkyl groups having 1 to 12 carbon atoms, and -CF ₃ , -CH ₂ CF ₃ , -CH ₂ CF ₂ CF ₃ , -CF ₂ CF ₂ CF _3, and the like. Of these, fluorine-containing alkyl groups having 1 to 8 carbon atoms are preferred.

The substituent of the " fluorine-containing alkyl group which may have a substituent group " in the above T ¹ is not particularly limited as long as it does not impair the effects of the present invention. Examples thereof include -OH, -COOH, -COOCH ₃ , NH ₂ , -COOCH ₂ CH ₃ , -COOCH ₂ CF ₃ , and the like.

When the fluorine-containing alkyl group which may have such a substituent has a substituent, it may have one substituent or two or more substituents. For example, the fluorine-containing alkyl group having 1 to 3 substituents And the like.

Specific examples of the group represented by the above formula (2-1) include, for example, groups represented by the following formulas.

Among the groups represented by the above formula (2-1), groups represented by the following formulas are preferable.

Further, as the group represented by the above formula (2-1), a group represented by the following formula is more preferred from the viewpoint of reactivity.

In the group represented by the formula (2-2), M is an aliphatic ring or a heteroaliphatic ring, T ² is the same or different and is H, F, an alkyl group which may have a substituent, A fluorine-containing alkyl group, and m is an integer of 3 or more.

The carbon number of the aliphatic ring and the hetero aliphatic ring represented by M is usually 3 to 100, preferably 3 to 50, more preferably 3 to 20.

Examples of the hetero atom constituting the heteroaliphatic ring include at least one selected from the group consisting of an oxygen atom, a nitrogen atom and a sulfur atom.

The above T ² is the same or different and represents H, F, an alkyl group which may have a substituent, or a fluorine-containing alkyl group which may have a substituent. The alkyl group of the "alkyl group which may have a substituent" A linear, branched or cyclic alkyl group having 1 to 12 carbon atoms, and examples thereof include a methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, sec- , A pentyl group, a cyclopentyl group, a hexyl group, a cyclohexyl group, an octyl group, and a cyclodecyl group. Among them, an alkyl group having 1 to 8 carbon atoms is preferable.

The substituent of the "alkyl group which may have a substituent" is not particularly limited as long as it does not adversely affect the performance of the fluorine-containing polymer of the present invention. Examples thereof include -OH, -COOH, -COOCH ₃ , -NH ₂ , -COOCH ₂ CH ₃ , and the like.

When the alkyl group which may have a substituent has a substituent, it may have one substituent or two or more substituents, and examples thereof include a form in which at least one of the above-exemplified substituents has 1 to 3 substituents .

As the fluorine-containing alkyl group of the "fluorine-containing alkyl group which may have a substituent" in the T ^2, there may be mentioned a linear, branched, or cyclic fluorinated alkyl group having 1 to 12, -CF _3, -CH ₂ CF ₃ , -CH ₂ CF ₂ CF ₃ , -CF ₂ CF ₂ CF _3, and the like. Of these, fluorine-containing alkyl groups having 1 to 8 carbon atoms are preferred.

The substituent of the " fluorine-containing alkyl group which may have a substituent group " in the above-mentioned T ² is not particularly limited as long as it does not adversely affect the performance of the fluorine-containing polymer of the present invention. -COOCH ₃ , -NH ₂ , -COOCH ₂ CH ₃ , -COOCH ₂ CF ₃ , and the like.

When the fluorine-containing alkyl group which may have such a substituent has a substituent, it may have one substituent or two or more substituents. For example, the fluorine-containing alkyl group having 1 to 3 substituents And the like.

M represents an integer of 3 or more, but the number of m is determined depending on the number of carbon atoms, the number and type of heteroatoms, etc. constituting the aliphatic ring or heteroaliphatic ring represented by M.

As the group represented by the above formula (2-2), a group represented by the following formula is preferable.

Wherein M and T ² are the same as in the formula (2-2). m ¹ is an integer of 3 or more, and the number of m ¹ is determined depending on the number of carbon atoms constituting the aliphatic ring or heteroaliphatic ring represented by M, the number and kinds of heteroatoms, and the like.

Among the groups represented by the above formula (2-2), groups represented by the following formulas are more preferable from the viewpoint of reactivity.

In the formulas, M, T ² and m ¹ are the same as the general formula described above.

More specific examples of the group represented by the above formula (2-2) include, for example, groups represented by the following formulas.

Among the groups represented by the above general formula (2-2), groups represented by the following formulas are preferable from the standpoints of reactivity being good and mechanical strength being imparted to the resulting cured product.

Examples of the epoxy compound include epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, cresol novolak type epoxy resin, alicyclic epoxy resin, alkylglycidyl ether, Cidyl ether, and the like. These may be used alone or in combination of two or more.

Specific examples of the epoxy compound include the following compounds.

In addition,

1,2-epoxy-4- (2-oxiranyl) cyclohexane adduct of 2,2-bis (hydroxymethyl) -1-butanol represented by the following formula (wherein n is about 1) . Further, solid bisphenol A type epoxy resins, solid bisphenol F type epoxy resins, and solid hydrogenated bisphenol A type epoxy resins can also be used. These may be used alone or in combination of two or more. Examples of commercially available products of these epoxy compounds include EHPE-3150 (manufactured by Daicel Chemical Industries), Epicote 1007 (manufactured by Mitsubishi Kagaku), Epikote 4007 (manufactured by Mitsubishi Kagaku), and YL7170 (manufactured by Mitsubishi Chemical Corporation).

Examples of the epoxy compound include, in addition to an alkyl monoglycidyl ether having 2 to 25 carbon atoms such as butyl glycidyl ether and 2-ethylhexyl glycidyl ether, butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether A polyoxyethylene alkyl ether, a polyoxyethylene alkyl ether, a polyoxyethylene alkyl ether, a polyoxyethylene alkyl ether, a polyoxyethylene alkyl ether, a polyoxyethylene alkyl ether, a polyoxyethylene alkyl ether, a polyoxyethylene alkyl ether, Ether, resorcine diglycidyl ether, pt-butylphenyl glycidyl ether, allyl glycidyl ether, tetrafluoropropyl glycidyl ether, octafluoropentyl glycidyl ether, dodecafluorooctyldiglyle Cyclopentene epoxide, cyclopentene epoxide, cyclohexene epoxide, cyclooctene epoxide, vinylcyclohexene dioxy, and the like can be used as long as it is at least one member selected from the group consisting of aliphatic, cycloaliphatic, .

As specific examples of the alicyclic epoxy resin,

(x12 is an integer of 1 to 40)

And the like.

Examples of the epoxy compound include fluorine-containing epoxy resins described in Japanese Patent Application Laid-Open Nos. 11-148878 and 2511287.

Examples of the fluorine-containing epoxy resin include compounds represented by the following formulas (I) to (IV):

[Wherein Rf represents a hydrogen atom,

{Wherein A is the formula:

Rf ² is a perfluoroalkyl group having 1 to 12 carbon atoms, p is an integer of 0 to 3, q is an integer of 0 to 3, r is 0 or ¹ , Rf ¹ is a perfluoroalkyl group having 1 to 10 carbon atoms, 1, s is an integer of 0 to 5, t is an integer of 0 to 5); B is the same as A or a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a fluoroalkyl group having 1 to 8 carbon atoms; Z is a hydrogen atom or a fluoroalkyl group having 1 to 18 carbon atoms; M,

(Wherein, R is the same or different, an alkyl group having 1 to 5, OH, CH _3, NH _2, a halogen atom, a fluoroalkyl group having 1 to 20 alkyl group; l _1, l ₂ and l ₃ are both zero Or an integer of 1 to 10 and the number of substituents R); x is an integer of 1 to 36}; and n is 0 or an arbitrary number of fluorine-containing polyfunctional epoxy resins.

As the Rf in the formulas (I) to (IV)

.

As the fluorine-containing epoxy resin, specifically,

(Wherein n7, n8 and n10 are 0 or an arbitrary positive number). Use of a fluorine-containing epoxy resin is preferable because the refractive index of the cured product can be lowered.

The epoxy compound is preferably a compound capable of dissolving the fluorine-containing polymer. When the above-mentioned epoxy compound can dissolve the fluorine-containing polymer, the curable composition of the present invention can be used as a curable composition of the following no-solvent type. From this point of view, the epoxy compound is a liquid at 25 占 폚, and the ratio of the dispersion term, the polarity term and the hydrogen bonding term in the solubility parameter is the point A (86, 7, 7) (50, 5, 45) and the point E (82, 5, 13) at the points C (50, 25, 25)

1 is a three-circle diagram showing the ratio of the dispersion term, the polarity term and the hydrogen bonding term in the solubility parameter of the epoxy compound.

In the present invention, the solubility parameter (SP value) is expressed by the following equation.

(SP value) ² = (dispersion term) ² + (polarity term) ² + (hydrogen bonding term) ²

Each epoxy compound has a numerical value of the inherent dispersion term, a numerical value of the polarity term and a numerical value of the hydrogen bonding term. In the present invention, those values described in the following documents are used.

DW Van Krevelen, "Properties of Polymers ", 3 ^rd Ed. ELSEVIER SCIENCE BV 1990

This is a method of dividing the epoxy compound into atomic units and calculating the SP value of the whole compound from the parameters derived from each of the atomic groups. The SP value of each epoxy compound was calculated by the method of Van Krevelen.

Surprisingly, the ratio of the dispersion term, the polarity term and the hydrogen bonding term in liquid at 25 占 폚 and in the three-circle diagram of Fig. 1 is in the range surrounded by the points A, B, C, D and E , The fluorine-containing polymer is dissolved in the epoxy compound, and a below-mentioned solventless curable composition is realized. The solventless curable composition does not contain an organic solvent, so that a cured product having excellent physical properties can be obtained, and there is an advantage that adverse effects on the environment are small.

Examples of the epoxy compound which is liquid at 25 占 폚 and is within the range surrounded by the points A, B, C, D and E shown in Fig. 1 include the following compounds.

The content of the epoxy compound is preferably 1 to 10,000 parts by mass with respect to 100 parts by mass of the fluorine-containing polymer. The upper limit of the content of the epoxy compound is more preferably 2000 parts by mass, further preferably 1000 parts by mass, and particularly preferably 900 parts by mass. The lower limit of the content of the epoxy compound is more preferably 1 part by mass, more preferably 5 parts by mass, still more preferably 10 parts by mass, still more preferably 100 parts by mass, most preferably 150 parts by mass.

When the composition is used as a solventless curable composition, an epoxy compound which is liquid at 25 占 폚 and which is in a range surrounded by points A, B, C, D and E shown in Fig. 1 is selected , And the content of the epoxy compound is preferably 1000 parts by mass with respect to 100 parts by mass of the fluorine-containing polymer. By adjusting the composition within the range, it is possible to adjust to the required viscosity.

Surprisingly, even in the three-dimensional view of Fig. 1, even in the case of the compounds belonging to the epoxy compound group (β) outside the range surrounded by the points A, B, C, D and E, Is dissolved in a solvent-free curable composition comprising a compound belonging to an epoxy compound group (?) And a fluorine-containing polymer which are in a range enclosed by respective points of point A, point B, point C, point D and point E, . That is, once the fluorine-containing polymer is dissolved in the epoxy compound belonging to the? Group, an epoxy compound belonging to the? -Group is added and dissolved to obtain a uniform solventless curing composition.

Surprisingly, even when an epoxy compound which is solid at 25 占 폚 and belongs to the? Group is used, the fluorine-containing polymer and the epoxy compound belonging to the? Group which is solid are uniformly dissolved by using an organic solvent, Or the like, is evaporated to obtain a transparent solid. Examples of such epoxy compounds include the following.

(Wherein n is about 1)

Examples of the epoxy compound which is outside the range surrounded by the points A, B, C, D, and E shown in Fig. 1 include the following compounds.

The curable composition of the present invention preferably contains an acid anhydride. As a result, the curable composition of the present invention can provide a cured product which is easy to thermally cure and exhibits further superior water vapor permeability, high modulus of elasticity, low coefficient of linear expansion, low refractive index and low dielectric constant.

Examples of the acid anhydrides include aromatic acid anhydrides, cyclic aliphatic acid anhydrides and aliphatic acid anhydrides. Specific examples include phthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic anhydride, ethylene glycol bis Trimellitate, glycerol tris trimellitate, maleic anhydride, tetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride (for example, 3-methyl-1,2,3,6-tetrahydrophthalic anhydride, Tetrahydrophthalic anhydride, 1,2,3,6-tetrahydrophthalic anhydride), endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, methylbutenyltetrahydrophthalic anhydride, dodecenylsuccinic anhydride, hexahydrophthalic anhydride, methylhexahydro (For example, 3-methyl-hexahydrophthalic anhydride, 4-methyl-hexahydrophthalic anhydride), succinic anhydride, methylcyclohexene dicar Alkylstyrene-maleic anhydride copolymers, chlorendic acid anhydrides, polyazelaic anhydrides, and the like.

Of these, 3-methyl-hexahydrophthalic anhydride and 4-methyl-hexahydrophthalic anhydride are preferable.

The content of the acid anhydride is preferably 1 equivalent (C = A '+ B) of the hydroxyl equivalent (A') calculated from the hydroxyl value (A) of the fluorine-containing polymer and the epoxy equivalent (B) It is preferably 0.6 to 1.4 equivalents based on the total weight of the composition.

As a result, a cured product having a higher level of low vapor permeability, a high elastic modulus, a low linear expansion coefficient, a low refractive index and a low dielectric constant can be obtained.

The upper limit of the acid anhydride equivalent is more preferably 1.3 equivalents, more preferably 1.2 equivalents, and particularly preferably 1.1 equivalents. The lower limit of the acid anhydride equivalent is more preferably 0.7 equivalents, more preferably 0.8 equivalents, and particularly preferably 0.85 equivalents.

The curable composition of the present invention is preferably a solventless curable composition. More specifically, the curable composition of the present invention, which does not contain an organic solvent having no radical reactive group, is advantageous in that the step of removing the solvent after curing the curable composition is unnecessary, the deterioration of the heat resistance by the residual solvent, It is preferable from the viewpoint that there is no adverse influence such as deterioration, cloudiness and cloudiness. Specific examples of the organic solvent not having a radical reactive group include aliphatic hydrocarbons having no radical reactive groups such as hexane, cyclohexane, heptane, octane, nonane, decane, undecane, dodecane, mineral spirit and the like; Aromatic hydrocarbons having no radical reactive groups such as benzene, toluene, xylene, naphthalene, and solvent naphtha; Examples of the solvent include methyl acetate, ethyl acetate, propyl acetate, n-butyl acetate, isobutyl acetate, isopropyl acetate, isobutyl acetate, cellosolve acetate, propylene glycol methyl ether acetate, carbitol acetate, diethyl oxalate, ethyl pyruvate, ethyl 2-hydroxybutyrate, ethyl acetoacetate, amyl acetate, methyl lactate, ethyl lactate, methyl 3-methoxypropionate, ethyl 3-methoxypropionate, methyl 2-hydroxyisobutyrate, ethyl 2-hydroxyisobutyrate Esters not having a radical reactive group of the formula Ketones having no radical reactive groups such as acetone, methyl ethyl ketone, cyclohexanone, methyl isobutyl ketone, 2-hexanone, cyclohexanone, methyl amino ketone and 2-heptanone; Methyl cellosolve acetate, ethyl cellosolve acetate, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, propylene glycol monomethyl ether acetate, propylene glycol mono Glycol ethers having no radical reactive groups such as ethyl ether acetate, propylene glycol monobutyl ether acetate, dipropylene glycol dimethyl ether, and ethylene glycol monoalkyl ether; Reactive radicals such as methanol, ethanol, isopropanol, n-butanol, isobutanol, t-butanol, sec-butanol, 3-pentanol, octyl alcohol, 3-methyl-3-methoxybutanol, Alcohols not possessed; Cyclic ethers having no radical reactive group such as tetrahydrofuran, tetrahydropyrane, dioxane, etc .; Amides having no radical reactive group such as N, N-dimethylformamide and N, N-dimethylacetamide; Ether alcohols having no radical reactive groups such as methyl cellosolve, cellosolve, isopropyl cellosolve, butyl cellosolve and diethylene glycol monomethyl ether; 1,1,2-trichloro-1,2,2-trifluoroethane, 1,2-dichloro-1,1,2,2-tetrafluoroethane, dimethyl sulfoxide and the like. Or mixed solvents of two or more of these solvents.

Examples of the organic solvent having no radical reactive group include fluorine-based solvents. Examples of the fluorine-based solvent include CH ₃ CCl ₂ F (HCFC-141b), CF ₃ CF ₂ CHCl ₂ / CClF ₂ CF ₂ CHClF mixture (HCFC-225), perfluorohexane, perfluoro tetrahydrofuran), methoxy-addition such as butane nona fluoro, methyl 1,3-bis-trifluoromethyl _{benzene, H (CF 2 CF 2)} n CH 2 OH (n: an integer of 1 to 3), F (CF ₂ ) _n CH ₂ OH (n is an integer of 1 to 5), CF ₃ CH (CF ₃ ) OH, and the like; Benzotrifluoride, perfluorobenzene, perfluoro (tributylamine), ClCF ₂ CFClCF ₂ CFCl ₂ , and the like. Two or more kinds of these fluorine-based solvents may also be used.

Examples of the organic solvent not having a radical reactive group include a mixed solvent of the above-mentioned non-fluorine solvent and fluorine solvent.

The curable composition of the present invention preferably does not contain any of the above-mentioned organic solvents having no radical reactive group.

The curable composition of the present invention preferably further comprises a curing accelerator. As a result, the obtained cured product is excellent in transparency. In addition, the hardness of the resulting cured product is also improved.

As the curing accelerator, a curing accelerator (curing catalyst) of an epoxy compound can be used. Examples of the curing accelerator include butylamine, octylamine, dibutylamine, monoethanolamine, diethanolamine, triethanolamine, diethylenetriamine, triethylenetetramine, oleylamine, cyclohexylamine, benzylamine, diethylaminopropylamine (Dimethylaminomethyl) phenol, morpholine, N-methylmorpholine, 1,8-diazabicyclo [5.4.0] diazabicyclo [ ) Undecene-7 (DBU), salts of these carboxylic acids and the like, low molecular weight polyamide resins obtained from excess polyamines and polybasic acids, reaction products of excess polyamines and epoxy compounds, tertiary amines, 3 An imidazole, a phosphine, a phosphonium salt, a sulfonium salt, a thiol compound, an aromatic dimethyl urea, an aliphatic dimethyl urea, and the like.

Among them, it is preferable to use an amine such as butylamine, octylamine, dibutylamine, monoethanolamine, diethanolamine, triethanolamine, diethylenetriamine, triethylenetetramine, oleylamine, cyclohexylamine, benzylamine, diethylaminopropylamine (Dimethylaminomethyl) phenol, morpholine, N-methylmorpholine, 1,8-diazabicyclo [5.4.0] diazabicyclo [ ) Undecene-7 (DBU), salts of these carboxylic acids and the like, low molecular weight polyamide resins obtained from excess polyamines and polybasic acids, and reaction products of excess polyamines and epoxy compounds, Diazabicyclo (5.4.0) undecene-7 (DBU) and salts thereof are more preferable.

The curing accelerator may be used alone or in combination of two or more. The content of the curing accelerator is preferably about 0.1 to 10 parts by mass, more preferably about 0.5 to 5 parts by mass based on 100 parts by mass of the total amount of the fluorine-containing polymer and the epoxy compound.

The curable composition of the present invention may contain various additives in addition to the above-described compounds, as needed, so long as the effect of the present invention is not impaired.

Examples of such an additive include a reaction inhibitor, a leveling agent, a viscosity adjuster, a light stabilizer, a water absorbent, a pigment, a dye, and a reinforcing agent.

Examples of the reaction inhibitor include 1-ethynyl-1-cyclohexanol, 2-ethynyl isopropanol, 2-methyl-3-butyne- Acetylenic alcohols such as 2-phenyl-3-butyn-2-ol; Alkenylsiloxanes such as 1,3,5,7-tetravinyltetramethylcyclotetrasiloxane; Maleate compounds such as diallyl fumarate, dimethyl fumarate and diethyl fumarate; Other examples include triallyl cyanurate and triazole. By combining the reaction inhibitor, the effect of liquefying the obtained composition or the pot life (usable time) of the obtained composition can be sufficiently elongated. The content of the reaction inhibitor is not particularly limited, but is preferably in the range of 10 to 50000 ppm (by mass) in the composition of the present invention.

The curable composition of the present invention is preferably a solventless type as described above, but it may contain an organic solvent depending on its use. The organic solvent is not particularly limited as long as each component constituting the curable composition of the present invention is uniformly dissolved or dispersed, but it is particularly preferable to uniformly dissolve the fluorine-containing polymer.

Specific examples include cellosolve solvents such as methyl cellosolve, ethyl cellosolve, methyl cellosolve acetate and ethyl cellosolve acetate; Ethyl acetate, ethyl lactate, ethyl lactate, ethyl lactate, ethyl lactate, ethyl lactate, ethyl lactate, ethyl lactate, ethyl lactate, ethyl lactate, Ester solvents such as methyl, ethyl 3-methoxypropionate, methyl 2-hydroxyisobutyrate and ethyl 2-hydroxyisobutyrate; Propylene glycol type solvents such as propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monobutyl ether, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monobutyl ether acetate and dipropylene glycol dimethyl ether ; Ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, 2-hexanone, cyclohexanone, methyl amino ketone and 2-heptanone; Alcohol solvents such as methanol, ethanol, n-propanol, isopropanol, n-butanol, isobutanol and isopentyl alcohol; Aromatic hydrocarbons such as toluene and xylene, and mixed solvents of two or more of these solvents.

Further, in order to improve the solubility of the fluorine-containing polymer, a fluorine-based solvent may be used if necessary. Examples of the fluorine-based solvent include those described above.

Among them, general-purpose solvents such as ketone solvents, acetic acid ester solvents, alcohol solvents and aromatic solvents are preferable from the viewpoints of paintability and productivity of coating.

The curable composition of the present invention may contain fine particles of an inorganic compound in order to increase the optical properties such as hardness, low refractive index, broad band and low reflectivity of the cured product depending on the application (for example, antireflection film, It may be blended.

The shape of the inorganic compound in the present invention may be ultrafine particles or colloidal sol. The amount of the inorganic fine particles to be added into the coating film may be about 50 to 75% by weight of the coating film weight.

When the compounding ratio of the inorganic compound fine particles is increased, the fluorine-containing component in the cured product is diluted and the effect of lowering the refractive index due to the fluorine-containing component is reduced. Instead, microvoids are formed in the coating film, The refractive index of the coated film is lowered to approach the refractive index of the air. Thus, a remarkably low refractive index material can be obtained by cooperation of the fluorine-containing component and the microvoid.

When the compounding ratio of the inorganic fine particles in the cured product is less than 50% by mass based on the coating weight, microvoids are not normally formed in the coating film, and the refractive index of the coating film can be lowered mainly by the action of the fluorine-containing component.

If the compounding ratio of the inorganic compound microparticles in the cured product exceeds 50% by mass based on the coating weight, microvoids are formed in the coating film depending on the composition of the cured product, and by the action of both the fluorine- The refractive index can be remarkably lowered. If the compounding ratio of the inorganic compound fine particles in the cured product exceeds 75% by mass based on the coating weight, the action of the fluorine-containing component remains, but the effect of lowering the refractive index of the microvoid becomes relatively strong, However, the physical strength is lowered.

The fine particles of the inorganic compound and the colloidal sol are not particularly limited, but a compound having a refractive index of 1.50 or less is preferable. Specific examples of the material include magnesium fluoride (refractive index 1.38), silicon oxide (refractive index 1.46), aluminum fluoride (refractive index 1.33-1.39), calcium fluoride (refractive index 1.44), lithium fluoride (refractive index 1.36-1.37), sodium fluoride (refractive index 1.32-1.34) , And thorium fluoride (refractive index: 1.45 to 1.50), and colloidal sol. The particle diameter (volume average particle diameter) of the fine particles or the colloidal sol is preferably sufficiently smaller than the wavelength of visible light in order to ensure transparency of the low refractive index material. Specifically, it is preferably 100 nm or less, particularly preferably 50 nm or less.

The volume average particle size of the fine particles is measured by using a particle size distribution measuring apparatus using a laser diffraction scattering method (for example, a particle size distribution measuring apparatus 9320HRA manufactured by Microtrac Inc.), dispersing in an organic solvent such as ethanol and measuring at room temperature .

When fine particles of an inorganic compound are used, it is preferable to use them in the form of an organic sol dispersed in advance in an organic dispersion medium in order not to lower the dispersion stability in the composition and the adhesion in a low refractive index material. In order to improve the dispersion stability of the inorganic fine particles and the adhesion in the low refractive index material in the composition, the surface of the inorganic fine particles may be previously modified by using various coupling agents and the like. Examples of the various coupling agents include organic substituted silicon compounds; Metal alkoxides such as aluminum, titanium, zirconium, antimony or mixtures thereof; Salts of organic acids; And a coordination compound bonded with a cytoplasmic compound.

The curable composition of the present invention differs depending on its use, but for applications such as sealing, if the viscosity at 30 캜 is too low, the drift is much and the handling property is deteriorated. Therefore, the viscosity is preferably 1 mPa · s More preferably not less than 5 mPa · s, and more preferably not less than 10 mPa · s, from the viewpoint that curing shrinkage upon curing is small, from the viewpoint of good film formability. From the viewpoint of good handling properties, it is preferably 20,000 mPa 占 퐏 or less, more preferably 5000 mPa 占 퐏 or less from the viewpoint that the curable composition spreads to the details at the time of molding, From the viewpoint of good smoothness, it is more preferable that the viscosity is 2000 mPa · s or less.

The curable composition of the present invention can be prepared by uniformly dissolving or dispersing the fluorine-containing polymer, the acid anhydride and other necessary components in the epoxy compound in the case of a solventless type. Finally, the fluorine-containing polymer, the acid anhydride and other necessary components may be uniformly dissolved or dispersed in the epoxy compound, and the mixing order of the components is not particularly limited.

The curable composition of the present invention may be either a dispertive dispersion in which the fluorine-containing polymer, the acid anhydride and other necessary components are dispersed in the epoxy compound, or a dissolving solution type. In order to form a uniform thin film , And it is also preferable that the film is formed in a uniform solution form since the film can be formed at a relatively low temperature.

As the coating method, a well-known method appropriate for the application can be adopted. For example, when it is necessary to control the film thickness, a roll coating method, a gravure coating method, a micro gravure coating method, a flow coating method, a bar coating method, a spray coating method, a die coating method, a spin coating method, Etc. may be employed.

The curable composition of the present invention can be easily cured by ordinary thermosetting conditions to obtain a cured product having low vapor permeability, high modulus of elasticity, low coefficient of linear expansion, and low refractive index. Thus, the cured product obtained by curing the curable composition in the present invention is also one of the present invention.

The curing (crosslinking) method of the curable composition of the present invention may be appropriately determined depending on the components to be used, and is generally cured at room temperature (for example, 20 ° C) to 200 ° C for 1 minute to 24 hours. It can also be cured under atmospheric pressure, pressurized, reduced pressure, or in air.

The curing method is not particularly limited, and a normal method in which a crosslinking reaction is initiated by steam cross-linking, pressure-forming, or heating can be adopted.

The curable composition of the present invention may be used for film formation, but is particularly useful as a molding material for various molded articles. As the molding method, extrusion molding, injection molding, compression molding, blow molding, transfer molding, stereolithography, nanoimprinting, vacuum molding and the like can be adopted.

The photo-curing resin composition of the present invention is useful as an optical material for an optical device such as an optical waveguide material and a sealing material for processing optical devices, and is also useful as an optical material for a display device such as an antireflection film. In addition, it can be used as a material for a sealing member for electronic semiconductors, a water resistant moisture resistant adhesive, and an adhesive for optical parts or devices.

The cured product obtained by curing the curable composition of the present invention can be suitably used as an optical member because of its excellent transparency. The cured product of the present invention preferably has a light transmittance of 80% or more. , More preferably 85% or more, and even more preferably 90% or more. The light transmittance of the cured product can be measured with a spectrophotometer (U-4100, manufactured by Hitachi, Ltd.) at a wavelength of 550 nm. The cured product of the present invention is not only excellent in transparency, but also exhibits a special performance as a sealing member as described above, and is thus particularly suitable as a sealing member for an optical element.

The cured product obtained by curing the curable composition of the present invention is also suitable for sealing applications which are excellent in heat resistance and require heat resistance such as sealing for power devices.

[Example]

Next, the present invention will be described by way of examples, but the present invention is not limited to these examples.

Measurement methods employed in this specification are summarized below.

(1) Fluorine content

The fluorine ion concentration was determined by a fluorine selective electrode method by an oxygen flask combustion method (mass%).

(2) ¹ H-NMR measurement

¹ H-NMR measurement conditions: 400 MHz (tetramethylsilane = 0 ppm)

(3) ¹⁹ F-NMR measurement

¹⁹ F-NMR measurement conditions: 376 MHz (trichlorofluoromethane = 0 ppm)

(4) Molecular weight and molecular weight distribution

The weight average molecular weight (Mw) and the number average molecular weight (Mn) were calculated from the data measured by gel permeation chromatography (GPC) using polystyrene as a standard sample and tetrahydrofuran (THF) as a solvent at a flow rate of 1 ml / Respectively.

(5) Glass transition temperature (Tg)

(First run) -low-temperature rise (second run) at a temperature range of -50 ° C to 200 ° C at a rate of 10 ° C / min using a DSC (differential scanning calorimeter) Was defined as Tg (占 폚).

(6) Melting point (Tm)

The temperature corresponding to the maximum value in the heat of fusion curve when the temperature was raised at a rate of 10 ° C / min using a DSC (differential scanning calorimeter) was defined as Tm (° C).

(7) IR analysis

Using a Fourier transform infrared spectrophotometer at room temperature.

(8) Hydroxyl value

It was measured according to JIS K 0070-1992.

(9) Refractive index (n _D )

Sodium D line was used as the light source and the Abbe's refractive index was measured at 25 캜.

The polymers used in Examples and their physical properties are shown in Table 4. The composition (molar ratio) of the polymer was determined by elemental analysis of fluorine, and the alternation ratio of fluoroolefin and vinyl ester was calculated from ¹ H-NMR, and the weight average molecular weight and the molecular weight distribution (Mw / Mn) . The glass transition temperature was also measured by DSC. The composition ratio of polymer B1 was also determined by using ¹⁹ F-NMR.

The polymers used in the examples were hydrolyzed and their hydroxyl value and refractive index were measured. The results are summarized in Table 5.

The polymers used in the other examples are shown below.

(Polymer E1)

Perfluoro (1,1,9,9-tetrahydro-2,5-bistrifluoromethyl-3,6-dioxanonenol) which is a fluorine-containing allyl ether:

Was used to obtain a fluorine-containing allyl ether polymer (a) (PAEH-1).

This polymer was subjected to ¹⁹ F-NMR analysis (measurement conditions: 282 MHz (trichlorofluoromethane: 0 ppm)) and ¹ H-NMR analysis (measurement condition: 300 MHz (tetramethylsilane = 0 ppm) (Measured at room temperature with a Fourier transform infrared spectrophotometer 1760X manufactured by Elmer Co.), it was found that the polymer was a fluorine-containing polymer having a hydroxyl group at the terminal of the side chain containing only the structural unit of the fluorine-containing allyl ether. The number-average molecular weight measured by GPC analysis was 9000, and the weight-average molecular weight was 22000. Other physical properties were as follows.

Tg = 31 占 폚, fluorine content (mass%) = 60, hydroxyl value (mgKOH / g) = 137, refractive index = 1.351.

This polymer is referred to as E1.

(Hydroxyl group-containing fluoropolymer D1)

Containing fluoropolymer D1 having the following composition was prepared. The hydroxyl group-containing fluoropolymer D1 had a weight average molecular weight of 50,000, a hydroxyl value of 66 mgKOH / g, and a refractive index of 1.420.

(Polymer F1)

A copolymer F1 having a 1,3-dioxane ring structural unit of 51 mol% and a tetrafluoroethylene unit of 49 mol% was produced. The refractive index was 1.324 and the hydroxyl value was almost 0 mg KOH / g.

(Polymer E2)

Polymer E2 (m: n = 50: 50) having the following structure was prepared. The identity of polymer E2 was determined by analysis of < ¹⁹ > F-NMR.

The fluorine-containing polymer E2 had a refractive index of 1.370 and a hydroxyl value of 63 mgKOH / g.

Example 1 (Solubility with? Group Compound)

A1-98 and B1-97 were added to the various epoxy compounds shown in Table 7 so as to be 10 mass%.

The appearance was visually observed, and the solubility was evaluated according to the following criteria. The results are shown in Table 7.

○: uniform dissolution

△: Residue with dissolved

X: Not dissolved

Examples 2 to 6 (Solubility with? Group Compound)

A solubility test was conducted in the same manner as in Example 1 except that the fluorine-containing polymers A3-34, A3-45, A3-86, A3-96 and E1 were used. The results are shown in Table 7.

Comparative Example 1 (Solubility with? Group Compound)

A solubility test was conducted in the same manner as in Example 1 except that the fluorine-containing polymer F1 was used. The results are shown in Table 7.

Comparative Example 2 (Solubility with? Group Compound)

A solubility test was conducted in the same manner as in Example 1 except that the fluorine-containing polymer D1 was used. The results are shown in Table 7.

Example 7 (Solubility with? -Group compound)

The fluorine-containing polymer A1-98 was added in an amount of 10% by mass based on the various epoxy compounds shown in Table 8, and the mixture was stirred at a temperature of 45 캜 for 24 hours in a tabletting machine. The appearance was visually observed, and the solubility was evaluated on the same basis as in Example 1. The results are shown in Table 8.

Example 8 (Solubility with? -Group compound)

A solubility test was conducted in the same manner as in Example 7 except that the fluorine-containing polymer E1 was used. The results are shown in Table 8.

Examples 9, 10 and 11 (after mixing in a group compound, homogeneously mixed with a group compound)

To the homogeneous compositions obtained in Examples 1, 4 and 6, 10% by mass of the epoxy compound belonging to the group? Shown in Table 9 was added, and the mixture was stirred at a temperature of 45 캜 for 24 hours in a tabletting machine. The appearance was visually observed, and the solubility was evaluated on the same basis as in Example 1. The results are shown in Table 9.

Example 12 (Examples 12-1 to 12-12)

Various curing compositions were prepared in the compositions shown in Table 10. The production procedure of the composition is the same as in the case of (1) uniformly dissolving the fluorine-containing polymer in the? -Group epoxy, (2) adding the epoxy group in the? (1) or (2) and then uniformly mixed with the solution of (1) or (2). (3). As the acid anhydride, HN-5500 manufactured by Hitachi Chemical Co., Ltd. was used. U-CAT SA-102 (DBU-octylate type catalyst), U-CAT 18X (special tertiary amine type catalyst), U-CAT 5003 (quaternary phosphonium salt type catalyst) Catalyst) was used.

When an acid anhydride is not used, (1) the fluorine-containing polymer is uniformly dissolved in the? Group epoxy, (2) when the? -Group epoxy is mixed, the fluorine-containing polymer is added to the homogeneous solution of (1) ) Curing catalyst was uniformly mixed with the solution of (1) or (2). (3) were mixed using a defoaming and stirring apparatus as in the case of using an acid anhydride.

When the U-CAT 5003 and U-CAT 18X were used, the curing condition was heated at 90 ° C for 2 hours and then at 130 ° C for 3 hours. When U-CAT SA-102 was used, it was heated at 100 占 폚 for 2 hours and then at 130 占 폚 for 6 hours.

The curability was evaluated according to the following criteria.

?: Uniform curing

?: Non-uniform hardening

X: Not hardened

In addition, the appearance was visually evaluated.

The results are shown in Table 10.

* The unit of composition in the table is the mass part.

Example 13 (Examples 13-1 to 13-2)

Various curable compositions were prepared in the compositions shown in Table 11. The fabricating procedure is the same as that of the twelfth embodiment.

The prepared curable composition was sandwiched between two glass plates which had been subjected to releasing treatment with Optool DSX manufactured by Daikin Industries, Ltd., with a spacer of 100 탆 interposed therebetween. The resultant was heated at 100 캜 for 2 hours and then heated and cured at 130 캜 for 6 hours. Various physical properties of the obtained cured product were measured by the following methods. The refractive index was measured by the above-mentioned method. The results are shown in Table 11.

(Elastic modulus and glass transition temperature (Tg))

Using a dynamic viscoelastic device, the measurement temperature was measured at 25 to 200 캜.

Tg is the peak temperature of tan?, And the elasticity is the value at 30 占 폚.

(Moisture permeability)

Measurement of the moisture permeability at 40 DEG C and 90% RH was carried out by the cup method in accordance with JIS Z0208.

(Dielectric loss tangent and dielectric constant)

Aluminum was deposited on both sides of the produced film (cured product) in vacuum to prepare a measurement sample. For this sample, capacitance and dielectric loss tangent were measured with an LCR meter at 30 DEG C and a frequency of 1 kHz. The relative dielectric constant was calculated from the film thickness and capacitance.

(Coefficient of linear expansion)

Using a thermomechanical analyzer (TMA, tensile mode), elongation of the film was measured under the conditions of a temperature range of 25 to 150 DEG C, a heating rate of 2 DEG C / min, and a chuck distance of 10 mm. From the obtained measurement results, the average thermal linear expansion coefficient was calculated using the following calculation formula.

Where L (30) is the sample length at 30 ° C, and L (50) is the sample length at 50 ° C.

L (30)) [(L (50) -L (30)) / (50-30)]

Comparative Example 3

Curable compositions were prepared in the compositions shown in Table 11, and various physical properties were measured in the same manner as in Example 13. [ The results are shown in Table 11.

* The unit of composition in the table is the mass part.

Example 14 (Examples 14-1 to 14-6)

Various curable compositions were prepared in the compositions shown in Table 12. The production procedure of the composition was such that (1) the fluorine-containing polymer was uniformly dissolved in the? -Group epoxy, (2) the curing catalyst was dissolved in the acid anhydride and then uniformly mixed in the solution of (1).

(2) were mixed using a defoaming and stirring apparatus.

The uniformity of the composition in the step (1) was judged by the following criteria.

○: uniform transparency

?: Unevenness

X: Not dissolved

The results are shown in Table 12.

As the acid anhydride, HN-5500 manufactured by Hitachi Chemical Co., Ltd. was used.

U-CAT 18X (special tertiary amine catalyst) or U-CAT SA-102 (DBU-octylate catalyst) manufactured by San A Pro Co., Ltd. was used as the epoxy curing catalyst.

When U-CAT 18X was used, the curing condition was heated at 90 ° C for 2 hours and then at 130 ° C for 3 hours. When U-CAT SA-102 was used, it was heated at 100 占 폚 for 2 hours and then at 130 占 폚 for 6 hours.

The curability was evaluated according to the following criteria.

?: Uniform curing

?: Non-uniform hardening

X: Not hardened

In addition, the appearance was visually evaluated.

Further, the refractive index of the cured product was measured by the above-mentioned method.

The results are shown in Table 12.

* The unit of composition in the table is the mass part.

Example 15 (Mixing using a solution, film-forming)

Epoxy-4- (2-oxiranyl) cyclohexane adduct of 2,2-bis (hydroxymethyl) -1-butanol, which is an epoxy compound belonging to the solid? Group at room temperature A) was dissolved in butyl acetate so as to be 10 mass%. Further, the fluorine-containing polymer E1 was dissolved in butyl acetate so as to be 10% by mass. Each of the solutions was mixed at a ratio shown in Table 13 (mass ratio), and cast film formation was performed at room temperature. Appearance was judged by the following criteria. The results are shown in Table 13.

?: Transparent uniformity

△: Partly cloudy

X: The whole was cloudy

Example 16 (Mixing using a solution, film-forming)

A cast film was formed in the same manner as in Example 15 except that the fluorine-containing polymer E1 was changed to A1-98. The results are shown in Table 13.

Comparative Example 4 (Mixing using a solution, film-forming)

A cast film was formed in the same manner as in Example 15 except that the fluorine-containing polymer E1 was changed to D1. The results are shown in Table 13.

Comparative Example 5 (Mixing using a solution, film formation)

A cast film was formed in the same manner as in Example 15 except that the fluorine-containing polymer E1 was changed to E2. The results are shown in Table 13.

Example 17

To the solution obtained in Example 15 (epoxy compound A: fluorine-containing polymer = 50: 50), 0.5% by mass of Sunaid SI-60L as an epoxy curing catalyst was added to the solid content. After casting at room temperature, it was cured at 90 DEG C for 2 hours and at 130 DEG C for 3 hours to obtain a film. The obtained film had a total light transmittance of 91% and a haze of 6.8.

The film was immersed in an acrylonitrile solution at room temperature, and the change in weight after 24 hours was examined. As a result, the degree of swelling was 3.2%.

The total light transmittance and haze were measured according to ASTM D1003 using a haze meter.

Example 18

To the solution obtained in Example 16 was added 0.5% by mass of Sun Aid SI-60L as an epoxy curing catalyst relative to the solid content. After casting at room temperature, it was cured at 90 DEG C for 2 hours and at 130 DEG C for 3 hours to obtain a film.

The film was immersed in an acrylonitrile solution at room temperature, and the change in weight after 24 hours was examined. As a result, the degree of swelling was about 4%.

Comparative Example 6

To the solution obtained in Example 15 was added 0.5% by mass of Sun Aid SI-60L as an epoxy curing catalyst with respect to the solid content.

After casting at room temperature, it was immersed in an acrylonitrile solution and dissolved.

Claims (9)

A fluorine-containing polymer and an epoxy compound having a hydroxyl value of 100 mgKOH / g or more and a refractive index of 1.42 or less,
The fluorine-containing polymer has a fluorine-containing olefin unit and a vinyl alcohol unit. The method according to claim 1,
The content of the fluorine-containing olefin unit in the fluorine-containing polymer is 30 mol% or more. A fluorine-containing polymer having a hydroxyl value of 100 mgKOH / g or more and a refractive index of 1.42 or less, and an epoxy compound,
The fluorine-containing polymer may be represented by the following formula (1):

(Wherein X ¹ , X ² and X ³ are the same or different and each represents H, F or fluoroalkyl group, R ¹ represents a divalent organic group which may have ether bond, x represents 0 or 1 And a unit based on a monomer represented by the following formula (I). 4. The method according to any one of claims 1 to 3,
Further comprising an acid anhydride. 4. The method according to any one of claims 1 to 3,
A curing composition, further comprising a cure accelerator. 4. The method according to any one of claims 1 to 3,
The epoxy compound is a liquid at 25 占 폚 and the ratio of the dispersion term, the polarity term and the hydrogen bonding term in the solubility parameter is the same as the point A (86,7,7), the point B (70,25, 5, 13) and the point C (50, 25, 25), the point D (50, 5, 45) and the point E (82, 5, 13). 4. The method according to any one of claims 1 to 3,
Wherein the epoxy compound is at least one compound selected from the group consisting of the following compounds.

4. The method according to any one of claims 1 to 3,
And does not comprise an organic solvent that does not have a radical reactive group. delete

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